Delta Air Lines

The airline has tapped advisers to explore a sale after its shares dropped more than 40% and it lost billions trying to turn around.

The Atlanta-based carrier employs around 15,000 pilots.

The carrier is said to plan to increase the number of flights that have free internet, starting in the new year.

The U.S. Department of Transportation has a hang-up with in-flight calls, perhaps enough to put an official kibosh on them – and soon.